Self-light emitting display unit and electronic device

ABSTRACT

A self-light emitting display unit capable of improving manufacturing yield is provided. Sizes of color pixel circuits corresponding to pixels for R, G, and B are respectively set unevenly within a pixel circuit according to a magnitude ratio of drive currents which allow color self-light emitting elements in the pixel to emit with a same light emission luminance. Thereby, the pattern densities of color pixel circuits respectively corresponding to the pixels for R, G, and B become even to each other, and the pattern defect rate as the whole pixel circuit is decreased.

CROSS REFERENCES TO RELATED APPLICATIONS

This is a Continuation Application of U.S. patent application Ser. No.12/457,314 filed Jun. 8, 2009, which in turn claims priority fromJapanese Application No.: 2008-159169, filed on Jun. 18, 2008, theentire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a self-light emitting display unitincluding a self-light emitting device and an electronic deviceincluding such a self-light emitting display unit.

2. Description of the Related Art

In recent years, a self-light emitting display unit (organic EL displayunit) using an organic EL (Electroluminescence) device as a self-lightemitting device has been actively developed. The organic EL device is adevice using phenomenon in which light is emitted if an electric fieldis applied to an organic thin film. Since the organic EL device is ableto be driven at, for example, an applied voltage of 10V or less, thepower consumption thereof is low. Further, since the organic EL deviceis a self-light emitting device as described above, an illuminationmember such as a liquid crystal device is not necessary, and thus weightsaving and thickness reducing are thereby easily realized. Further,since the response speed of the organic EL device is enormously high,that is, about several μs, there is an advantage that a residual imagein displaying videos is not generated.

Of the organic EL display unit using such an organic EL device,specially, an active matrix organic EL display unit in which a thin filmtransistor (TFT) as a drive element and the like are integrally formedin each pixel is actively developed (for example, refer to JapaneseUnexamined Patent Application Publication No. 2007-310311).

SUMMARY OF THE INVENTION

In the foregoing Japanese Unexamined Patent Application Publication No.2007-310311 and the like, a pixel circuit formed in each pixel isdisclosed. In some cases, sizes of a drive transistor and an accumulatedcapacitative element of respective pixel circuits for each color, R(red), G (green), and B (blue) differ according to each necessary sizeof a display drive current. In result, in a pixel circuit for a specificcolor, the pixel pattern density becomes high, and thus the patterndefect rate is increased due to dust or the like. In the case where thepattern defect rate is increased, the manufacturing yield is lowered.

The foregoing disadvantage exists not only in the case that theself-light emitting device is the organic EL device, but also in thecase of an inorganic EL device or an LED (Light Emitting Diode).

In view of the foregoing disadvantage, in the invention, it is desirableto provide a self-light emitting display unit and an electronic devicecapable of improving the manufacturing yield.

According to an embodiment of the invention, there is provided a firstself-light emitting display unit including a pixel layer in which aplurality of pixels are formed, each of the pixels being configured of aplurality of color pixels each having a color self-light emittingelement, and a pixel circuit layer in which a plurality of pixelcircuits are formed, each of the pixel circuits being configured of aplurality of color pixel circuits which drive the color pixels,respectively. Sizes of the color pixel circuits are set unevenly withinthe pixel circuit according to a magnitude ratio of drive currents whichallow the color self-light emitting elements in the pixel to emit with asame light emission luminance.

According to an embodiment of the invention, there is provided a firstelectronic device including the foregoing first self-light emittingdisplay unit having a display function.

In the first self-light emitting display unit and the first electronicdevice of the embodiments of the invention, sizes of the color pixelcircuits are set unevenly within the pixel circuit according to amagnitude ratio of drive currents which allow the color self-lightemitting elements in the pixel to emit with a same light emissionluminance Thereby, even if device sizes in the pixel circuits aredifferent from each other according to the magnitude of drive currents,in the respective pixels for each color, the pixel pattern densities inthe corresponding pixel circuits are even to each other. Thereby,increase of the pattern defect rate due to increase of the pixel patterndensity in the pixel circuit for a specific color is avoided, and thepattern defect rate as the whole pixel circuit is decreased.

According to an embodiment of the invention, there is provided a secondself-light emitting display unit including a pixel layer in which aplurality of pixels are formed, each of the pixels being configured of aplurality of color pixels each having a color self-light emittingelement, and a pixel circuit layer in which a plurality of pixelcircuits are formed, each of the pixel circuits being configured of aplurality of color pixel circuits which drive the color pixels,respectively. Each of the color pixel circuits includes a drivetransistor having an active layer and a gate electrode. Sizes of thecolor pixel circuits are set unevenly within the pixel circuit accordingto an area ratio between overlapping regions, each defined as a regionwhere the active layer and the gate electrode in the drive transistoroverlap one another.

According to an embodiment of the invention, there is provided a secondelectronic device including the foregoing second self-light emittingdisplay unit having a display function.

In the second self-light emitting display unit and the second electronicdevice of the embodiments of the invention, sizes of the color pixelcircuits are set unevenly within the pixel circuit according to an arearatio between overlapping regions, each defined as a region where theactive layer and the gate electrode in the drive transistor overlap oneanother. Thereby, even if device sizes of the drive transistors aredifferent from each other according to the area between overlappingregions, in the respective pixels for each color, the pixel patterndensities in the corresponding pixel circuits are even to each other.Thereby, increase of the pattern defect rate due to increase of thepixel pattern density in the pixel circuit for a specific color isavoided, and the pattern defect rate as the whole pixel circuit isdecreased.

According to an embodiment of the invention, there is provided a thirdself-light emitting display unit including a pixel layer in which aplurality of pixels are formed, each of the pixels being configured of aplurality of color pixels each having a color self-light emittingelement; and a pixel circuit layer in which a plurality of pixelcircuits are formed, each of the pixel circuits being configured of aplurality of color pixel circuits which drive the color pixels,respectively. Each of the color pixel circuits includes a capacitiveelement. Further, sizes of the color pixel circuits are set unevenlywithin the pixel circuit according to an area ratio between capacitiveelements in the color pixel circuits.

According to an embodiment of the invention, there is provided a thirdelectronic device including the foregoing third self-light emittingdisplay unit having a display function.

In the third self-light emitting display unit and the third electronicdevice of the embodiments of the invention, sizes of the color pixelcircuits are set unevenly within the pixel circuit according to an arearatio between capacitive elements in the color pixel circuits. Thereby,even if device sizes of the accumulated capacitative elements aredifferent from each other according to the area of the accumulatedcapacitative element, in the respective pixels for each color, the pixelpattern densities in the corresponding pixel circuits are even to eachother. Thereby, increase of the pattern defect rate due to increase ofthe pixel pattern density in the pixel circuit for a specific color isavoided, and the pattern defect rate as the whole pixel circuit isdecreased.

According to the first self-light emitting display unit or the firstelectronic device of the embodiments of the invention, sizes of thecolor pixel circuits are set unevenly within the pixel circuit accordingto a magnitude ratio of drive currents which allow the color self-lightemitting elements in the pixel to emit with a same light emissionluminance. Thereby, the pixel pattern densities of the correspondingpixel circuits in each pixel for each color become even to each other,and the pattern defect rate as the whole pixel circuit is able to bedecreased. Accordingly, the manufacturing yield is able to be improved.

According to the second self-light emitting display unit and the secondelectronic device of the embodiments of the invention, sizes of thecolor pixel circuits are set unevenly within the pixel circuit accordingto an area ratio between overlapping regions, each defined as a regionwhere an active layer and a gate electrode in the drive transistoroverlap one another. Thus, the pixel pattern densities in thecorresponding pixel circuits in each pixel for each color become even toeach other, and the pattern defect rate as the whole pixel circuit isable to be decreased. Accordingly, the manufacturing yield is able to beimproved.

According to the third self-light emitting display unit and the thirdelectronic device of the embodiments of the invention, sizes of thecolor pixel circuits are set unevenly within the pixel circuit accordingto an area ratio between capacitive elements in the color pixelcircuits. Thus, the pixel pattern densities in the corresponding pixelcircuits in each pixel for each color are even to each other, and thepattern defect rate as the whole pixel circuit is able to be decreased.Accordingly, the manufacturing yield is able to be improved.

Other and further objects, features and advantages of the invention willappear more fully from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a whole structure of a self-lightemitting display unit according to a first embodiment of the invention;

FIG. 2 is a circuit diagram illustrating a structural example of a pixelcircuit in each pixel illustrated in FIG. 1;

FIG. 3 is a plan view illustrating a structure of the pixel circuitillustrated in FIG. 2;

FIG. 4 is a plan view illustrating a structural example of a pixelcircuit layer of a pixel for each color according to the firstembodiment;

FIG. 5 is a plan view illustrating a structural example of a self-lightemitting device of a pixel for each color according to the firstembodiment;

FIG. 6 is a cross sectional view illustrating a cross sectionalstructural example of the pixel circuit layer and the self-lightemitting device illustrated in FIG. 4 and FIG. 5;

FIG. 7 is a timing waveform chart illustrating a display drive operationexample in the pixel circuit illustrated in FIG. 2;

FIG. 8 is a plan view illustrating an existing structure of a pixelcircuit layer of a pixel for each color according to a comparativeexample;

FIG. 9 is a plan view illustrating an existing structure of a self-lightemitting device of a pixel for each color according to the comparativeexample;

FIG. 10 is a plan view illustrating a structural example of a self-lightemitting device of a pixel for each color according to a secondembodiment;

FIG. 11 is a plan view for explaining a parasitic capacity componentthat may be generated in the pixel circuit layer and the self-lightemitting device of the first embodiment;

FIGS. 12A and 12B are schematic cross sectional views for explaining theparasitic capacity component illustrated in FIG. 11;

FIG. 13 is a circuit diagram for explaining the parasitic capacitycomponent illustrated in FIG. 11;

FIG. 14 is a timing waveform chart for explaining crosstalk phenomenoncaused by the parasitic capacity component illustrated in FIG. 11;

FIG. 15 is a plan view illustrating a structural example of a self-lightemitting device of a pixel for each color according to a thirdembodiment;

FIG. 16 is a plan view illustrating a structural example of a pixelcircuit layer of a pixel for each color according to a fourthembodiment;

FIG. 17 is a plan view illustrating another structural example of apixel circuit layer of a pixel for each color according to the fourthembodiment;

FIG. 18 is a perspective view illustrating an appearance of a firstapplication example of the self-light emitting display unit of theinvention;

FIG. 19A is a perspective view illustrating an appearance viewed fromthe front side of a second application example, and FIG. 19B is aperspective view illustrating an appearance viewed from the rear side ofthe second application example;

FIG. 20 is a perspective view illustrating an appearance of a thirdapplication example;

FIG. 21 is a perspective view illustrating an appearance of a fourthapplication example;

FIG. 22A is an elevation view of a fifth application example unclosed,FIG. 22B is a side view thereof, FIG. 22C is an elevation view of thefifth application example closed, FIG. 22D is a left side view thereof,FIG. 22E is a right side view thereof, FIG. 22F is a top view thereof,and FIG. 22G is a bottom view thereof;

FIG. 23 is a circuit diagram illustrating a structure of a pixel circuitaccording to a modified example of the invention;

FIG. 24 is a plan view illustrating a structure of the pixel circuitillustrated in FIG. 23; and

FIG. 25 is a plan view illustrating a structure of a self-light emittingdevice corresponding to the pixel circuit illustrated in FIG. 23.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the invention will be hereinafter described in detailwith reference to the drawings.

First Embodiment

FIG. 1 illustrates an overall structure of a self-light emitting displayunit (organic EL display unit 1) according to a first embodiment of theinvention. The organic EL display unit 1 includes a pixel array section2 having pixels 20 that are two-dimensionally arranged in the state of amatrix, and an electric power scanning circuit 31, a writing scanningcircuit 32, and a horizontal drive circuit 33 that are arranged on theperiphery of the pixel array section 2. In the m*n pixel arrangement ofthe pixel array section 2, electric power supply lines VL-1 to VL-m andscanning lines WL-1 to WL-m are connected to pixels for every pixel row,and signal lines DL-1 to DL-n are connected to pixels for every pixelcolumn.

The pixel array section 2 is formed on a transparent insulated substrate(not illustrated) made of, for example, a glass plate or the like, andhas a flat type panel structure. In each pixel 20 in the pixel arraysection 2, as described later, a pixel circuit using an amorphoussilicon TFT (Thin Film Transistor) or a low temperature polysilicon TFTis formed. In the pixel circuit, as described later, an organic ELdevice as a self-light emitting device and a pixel circuit layercomposed of a metal layer, a semiconductor layer, an insulating layerand the like are included. In the case where the low temperaturepolysilicon TFT is used in the pixel circuit, the electric powerscanning circuit 31, the writing scanning circuit 32, and the horizontaldrive circuit 33 are also able to be mounted on the panel (substrate) onwhich the pixel array section 2 is formed.

The writing scanning circuit 32 is a circuit for line-sequentiallyscanning the pixel 20 in units of row by line-sequentially supplying ascanning signal to the scanning lines WL-1 to WL-m.

The electric power scanning circuit 31 is a circuit for supplying anelectric power voltage to the electric power supply lines VL-1 to VL-mbeing synchronized with the line sequential scanning by the writingscanning circuit 32.

The horizontal drive circuit 33 is a circuit for supplying asappropriate a display drive voltage based on a picture signal accordingto luminance information (specifically, a signal potential(after-mentioned signal potential Vsig) and a reference potential(after-mentioned reference potential Vo)) to the signal lines DL-1 toDL-n.

FIG. 2 is a circuit diagram illustrating a structural example of thepixel circuit formed in each pixel 20. The pixel circuit includes awriting transistor 21, a drive transistor 22, an accumulatedcapacitative element 23, and an organic EL device 24. The electric powersupply line VL, the scanning line WL, and the signal line DL areconnected to the pixel circuit. The writing transistor 21 and the drivetransistor 22 are respectively configured of an N-channel type TFT.Conductivity type combination of the writing transistor 21 and the drivetransistor 22 is not limited thereto, but other combination may beadopted.

In the writing transistor 21, a gate is connected to a scanning line WL,a source is connected to a signal line DL, and a drain is connected to agate of the drive transistor 22 and one end of an accumulatedcapacitative element 23. The writing transistor 21 becomes in the stateof conduction according to the scanning signal applied from the writingscanning circuit 32 to the gate through the scanning line WL, andthereby samples the signal potential Vsig of the picture signal suppliedfrom the horizontal drive circuit 33 through the signal line DL andwrites the signal potential into the pixel 20. The written signalpotential Vsig (display drive current) is retained in the accumulatedcapacitative element 23.

In the drive transistor 22, a source is connected to the other end ofthe accumulated capacitative element 23 and an anode (anode electrode)of the organic EL device 24, and a drain is connected to the powersource supply line VL. In the case where the potential of the electricpower supply line VL is in the state of “H (high),” the drive transistor22 is supplied with a current through the electric power supply line VL.Thereby, the drive transistor 22 supplies the display drive currentaccording to the signal potential Vsig retained in the accumulatedcapacitative element 23 to the organic EL device 24, and current-drivesthe organic EL device 24.

The accumulated capacitative element 23 accumulates the display drivecurrent as described above.

In the organic EL device 24, a cathode (cathode electrode) is connectedto a common electric power supply line 25 commonly connected to allpixels 20.

A description will be given in detail of planar structural examples anda cross sectional structural example of the pixel circuit illustrated inFIG. 2 with reference to FIG. 3 to FIG. 6.

FIG. 3 illustrates a planar structural example of a pixel circuit (pixelcircuit layer) in one pixel 20. The pixel circuit has a laminatedstructure in which, a first metal layer M1, a polysilicon layer P1, anda second metal layer M2 are respectively layered with an insulatinglayer (not illustrated) (composed of, for example, silicon oxide (SiO₂)or the like) in between in this order from the substrate side (notillustrated). The first metal layer M1 and the second metal layer M2 arerespectively composed of, for example, aluminum (Al), copper (Cu) or thelike. The first metal layer M1 and the second metal layer M2 areelectrically connected with a connection contact section CT 12 inbetween. The second metal layer M2 and the polysilicon layer P1 areelectrically connected with a connection contact section CT 2P inbetween.

Specifically, the signal line DL is configured of the first metal layerM1 and the second metal layer M2. The electric power supply line VL andthe scanning line WL are respectively configured of the second metallayer M2.

The writing transistor 21 and the drive transistor 22 are respectivelyconfigured of the first metal layer M1, the second metal layer M2, thepolysilicon layer P1, and the insulating layer (not illustrated). Theaccumulated capacitative element 23 is configured of the first metallayer M1, the polysilicon layer P1, and the insulating layer (notillustrated).

The organic EL device 24 is connected to the pixel circuit layerillustrated in FIG. 3 through a connection contact section CT23structuring a node Na.

FIG. 4 illustrates a planar structural example of a pixel circuit (pixelcircuit layer) of pixels for each color 20R1, 20G1, and 20B1. In thefigure, the red pixel 20R1, the green pixel 20G1, and the blue pixel20B1 are arranged in this order along the electric power supply line VLand the scanning line WL. That is, the pixel 20 is configured of thepixels 20R1, 20G1, and 20B1 for R (red), G (green), and B (blue). Signalline (signal lines DLr, DLg, and DLb) for supplying the display drivevoltage based on the picture signal are respectively connected for everypixel 20R1, 20G1, and 20B1 for R, G, and B.

In the red pixel 20R1, as illustrated in FIG. 3, a writing transistor21R1, a drive transistor 22R1, an accumulated capacitative element 23R1and the like are formed. The electric power supply line VL, the scanningline WL, and the signal line DLr are connected to the red pixel 20R1.Similarly, in the green pixel 20G1, a writing transistor 21G1, a drivetransistor 22G1, and an accumulated capacitative element 23G1 and thelike are formed. The electric power supply line VL, the scanning lineWL, and the signal line DLg are connected to the green pixel 20G1.Further, in the blue pixel 20B1, a writing transistor 21B1, a drivetransistor 22B1, an accumulated capacitative element 23B1 and the likeare formed. The electric power supply line VL, the scanning line WL, andthe signal line DLb are connected to the blue pixel 20B1.

In the pixel circuit layer of this embodiment, sizes of the color pixelcircuits 26R, 26G, and 26B corresponding to the pixels 20R1, 20G1, and20B1 for R, G, and B are respectively set unevenly within the pixelcircuit according to a ratio of a size of the display drive currentnecessary for each organic EL device 24 to obtain the same lightemission luminance. Specifically, sizes of the color pixel circuits 26R,26G, and 26B are respectively set unevenly within the pixel circuitaccording to an area ratio between the color pixel circuits, of opposingregions (overlapping regions) of an active layer (polysilicon layer P1)and a gate electrode (second metal layer M2) in the drive transistors22R1, 22G1, and 22B1 in the pixel circuits. Further, sizes of the colorpixel circuits 26R, 26G, and 26B are set unevenly within the pixelcircuit according to an area ratio between the color pixel circuits, ofthe accumulated capacitative elements 23R1, 23G1, and 23B1. However, thetotal pixel size of the red pixel 20R, the green pixel 20G, and the bluepixel 20B (total pixel size 26RGB: for example, about 100 μm) is set tobe the same as an existing total pixel size.

Sizes of the color pixel circuits 26R, 26G, and 26B are expressed by thefollowing expression 1:(the pixel size 26G corresponding to the pixel 20G1 for G)<(the pixelsize 26R corresponding to the pixel 20R1 for R)<(the pixel size 26Bcorresponding to the pixel 20B1 for B)  1

In the pixel layer of this embodiment, as a planar structural exampleillustrated in FIG. 5, respective sizes 27R1, 27G1, and 27B1 of pixels20R1, 20G1, and 20B1 for R, G, and B are set evenly within the pixel,and formation positions of pixels 20R1, 20G1, and 20B1 for R, G, and Bare set evenly within the pixel. Specifically, arrangement pitches ofanode electrodes 281R1, 281G1, and 281B1 and light emitting layers 29R1,29G1, and 29B1 are respectively set evenly within the pixel, andformation positions of anode electrodes 281R1, 281G1, and 281B1 andlight emitting layers 29R1, 29G1, and 29B1 are respectively set evenlywithin the pixel. More specifically, arrangement pitches of anodeelectrodes 281R1, 281G1, and 281B1 are respectively set evenly withinthe pixel, and formation positions of anode electrodes 281R1, 281G1, and281B1, and further, arrangement pitches of light emitting layers 29R1,29G1, and 29B1 are respectively set evenly within the pixel, andformation positions of light emitting layers 29R1, 29G1, and 29B1 arerespectively set evenly within the pixel. The anode electrodes 281R1,281G1, and 281B1 are, for example, configured of an electrode in whichITO (indium tin complex oxide) is layered on silver (Ag) or an Ag alloy.

As illustrated in a cross sectional structural example of FIG. 6 (crosssectional structural example taken along II-II in FIG. 5), the organicEL device 24 has a laminated structure including the anode electrode281R1 and the like, the light emitting layer 29R1 and the like, acathode electrode 282 common to each pixel, an auxiliary electrodesection 280-1 electrically connected to the cathode electrode 282, andan insulating layer 42, and is formed on a pixel circuit layer 41. Thecathode electrode 282 is configured of a single substance or an alloy ofa metal element such as aluminum (Al), magnesium (Mg), calcium (Ca), andsodium (Na).

Next, a description will be given in detail of operations and effects ofthe organic EL display unit 1 of this embodiment.

First, a description will be given of a basic operation of the organicEL display unit 1 (operation of display-driving the pixel circuit ofeach pixel 20) with reference to FIG. 7 in addition to FIG. 2. FIG. 7 isa timing waveform chart illustrating a display drive operation examplein the pixel circuit illustrated in FIG. 2. In FIG. 7, (A) illustrates ascanning line potential V (WL), (B) illustrates an electric power supplyline potential V (VL), (C) illustrates a signal line potential V (DL),(D) illustrates a gate potential Vg of the drive transistor 22, and (E)illustrates a source potential Vs of the drive transistor 22.

Light Emission Time Period T0

First, in light emission time period T0 before timing t1, the organic ELdevice 24 is in the state of light emission (light emission timeperiod). In the light emission time period T0, the potential V (VL) ofthe electric power supply line VL is in the state of high potential (“H”state), and a display drive current (drain-to-source current) issupplied from the electric power supply line VL to the organic EL device24 through the drive transistor 22. Thus, the organic EL device 24 emitslight at luminance according to the display drive current.

Threshold Value Correction Preparatory Time Period T1

Next, in the timing t1, the state becomes a new field of line sequentialscanning. At this time, the potential V (VL) of the electric powersupply line VL is shifted from a high potential to a potentialsufficiently lower than the reference potential Vo of the signal line DL(“L (low)” state), and the source potential Vs of the drive transistor22 becomes a potential almost even to this low potential.

Next, in timing t2, the scanning signal is outputted from the writingscanning circuit 32, and the potential of the scanning line DL isshifted to the high potential side. Thereby, the writing transistor 21becomes in the state of conduction. At this time, since the referencepotential Vo is supplied from the horizontal drive circuit 33 to thesignal line DL, the gate potential Vg of the drive transistor 22 becomesthe reference potential Vo. At this time, the source potential Vs of thedrive transistor 22 is a potential sufficiently lower than the referencepotential Vo.

The low potential is set so that a gate-to-source voltage Vgs of thedrive transistor 22 is larger than a threshold value voltage Vth of thedrive transistor 22. As described above, respective initialization isperformed so that the gate potential Vg of the drive transistor 22becomes the reference potential Vo and the source potential Vs becomesthe low potential, and thereby preparation of the threshold valuevoltage correction operation is completed.

Threshold Value Correction Time Period T2

Next, in timing t3, the potential V (VL) of the electric power supplyline VL is shifted from low potential to high potential. The sourcepotential Vs of the drive transistor 22 starts to be increased. In duecourse of time, the gate-to-source voltage Vgs of the drive transistor22 becomes the threshold value voltage Vth of the drive transistor 22. Avoltage corresponding to the threshold value voltage Vth is written inthe accumulated capacitative element 23.

For convenience, time period during which the voltage corresponding tothe threshold value voltage Vth is written in the accumulatedcapacitative element 23 is called threshold value correction time periodT2. In the threshold value correction time period T2, to make a currentonly flow to the accumulated capacitative element 23 side and preventthe current from being flown to the organic EL device 24 side, thepotential of the common electric power supply line 25 is set so that theorganic EL device 24 becomes in the state of cutoff.

Sampling Time Period/mobility Correction Time Period T3

Next, in timing t4, output of the scanning signal from the writingscanning circuit 32 is stopped, and the potential V (WL) of the scanningline WL is shifted to the low potential side. Thereby, the writingtransistor 21 becomes in the state of non-conduction. At this time, thegate of the drive transistor 22 becomes in the state of floating.However, since the gate-to-source voltage Vgs is even to the thresholdvalue voltage Vth of the drive transistor 22, the drive transistor 22 isin the state of cutoff. Thus, the drain-to-source current is not flown.

Next, in timing t5, the potential V (DL) of the signal line DL isshifted from the reference potential Vo to the signal potential Vsig ofthe picture signal. In timing t6, the scanning signal is again outputtedfrom the writing scanning circuit 32, and the potential V (WL) of thescanning line WL is shifted to the high potential side. Thereby, thewriting transistor 21 becomes in the state of conduction, and the signalpotential Vsig of the picture signal is sampled.

Due to sampling of the signal potential Vsig by the writing transistor21, the gate potential Vg of the drive transistor 22 becomes the signalpotential Vsig. At this time, since the organic EL device 24 is firstlyin the state of cutoff (high impedance state). Thus, the drain-to-sourcecurrent of the drive transistor 22 is flown into a parasiticcapacitative element (not illustrated) connected in parallel to theorganic EL device 24, and charging the parasitic capacitative element isstarted.

Due to charging the parasitic capacitative element, the source potentialVs of the drive transistor 22 starts to be increased. In due course oftime, the gate-to-source voltage Vgs of the drive transistor 22 becomes(Vsig+Vth−ΔV). That is, the increase portion ΔV of the source potentialVs is deducted from the voltage retained in the accumulated capacitativeelement 23 (Vsig+Vth), that is, the increase portion ΔV of the sourcepotential Vs acts to discharge the electric charge of the accumulatedcapacitative element 23, resulting in the state of negative feedback.Thus, the increase portion ΔV of the source potential Vs becomes afeedback amount of negative feedback.

As described above, the drain-to-source current flowing through thedrive transistor 22 is negatively feed-backed to gate input of the drivetransistor 22, that is, the gate-to-source voltage Vgs, and therebymobility correction in which dependability on mobility μ of thedrain-to-source current of the drive transistor 22 is negated, that is,mobility correction in which variation of the mobility μ for every pixelis corrected is performed.

More specifically, as the signal potential Vsig of the picture signal isincreased, the drain-to-source current is increased, and the absolutevalue of the feedback amount of negative feedback (correction amount) ΔVis increased as well. Thus, mobility correction according to lightemission luminance level is able to be performed. Further, in the casewhere the signal potential Vsig of the picture signal is constant, asthe mobility μ of the drive transistor 22 is increased, the absolutevalue of the feedback amount of negative feedback ΔV is increased aswell, and thus variation of the mobility μ for every pixel is negated.

Light Emission Time Period T4 (T0)

Next, in timing t7, output of the scanning signal from the writingscanning circuit 32 is stopped, and the potential V (WL) of the scanningline WL is shifted to the low potential side. Thereby, the writingtransistor 21 becomes in the state of non-conduction. Thereby, the gateof the drive transistor 22 is detached from the signal line DL. At thesame time, a drain-to-source current starts to flow in the organic ELdevice 24, and thereby the anode potential of the organic EL device 24is increased according to the drain-to-source current.

Such increase of the anode potential of the organic EL device 24 isprecisely increase of the source potential Vs of the drive transistor22. Therefore, in the case where the source potential Vs of the drivetransistor 22 is increased, due to boot strap operation of theaccumulated capacitative element 23, the gate potential Vg of the drivetransistor 22 is increased in conjunction therewith. At this time, theincrease amount of the gate potential Vg is even to the increase amountof the source potential Vs. Thus, in light emission time period T4, thegate-to-source voltage Vgs of the drive transistor 22 is constantlymaintained as (Vin+Vth−ΔV).

Display-driving the pixel circuit in each pixel 20 described above isline-sequentially performed in the pixel array section 2, and therebyimage display based on the picture signal is performed as the wholeorganic EL display unit 1 illustrated in FIG. 1.

Next, a description will be given in detail of operations and effects ofcharacteristic sections of the invention with reference to FIG. 8 andFIG. 9 in addition to FIG. 4 and FIG. 5 in comparison with a comparativeexample. FIG. 8 and FIG. 9 illustrate planar structural examples of apixel circuit layer and an organic EL device of pixels for each color100R, 100G, and 100B in an existing organic EL display unit according tothe comparative example. In the red pixel 100R, a writing transistor101R, a drive transistor 102R, an accumulated capacitative element 103Rand the like are formed. The electric power supply line VL, the scanningline WL, and the signal line DLr are connected to the red pixel 100R.Similarly, in the green pixel 100G, a writing transistor 101G, a drivetransistor 102G, an accumulated capacitative element 103G and the likeare formed. The electric power supply line VL, the scanning line WL, andthe signal line DLg are connected to the green pixel 100G. Further, inthe blue pixel 100B, a writing transistor 101B, a drive transistor 102B,an accumulated capacitative element 103B and the like are formed. Theelectric power supply line VL, the scanning line WL, and the signal lineDLb are connected to the blue pixel 100B.

As illustrated in FIG. 8, in the organic EL display unit according tothe comparative example, sizes of the color pixel circuits 106R, 106G,and 106B respectively corresponding to the pixels 100R, 100G, and 100Bfor R, G, and B are respectively set evenly within the pixel circuit.Further, sizes of the drive transistors 102R, 102G, and 102B and sizesof the accumulated capacitative elements 103R, 103G, and 103B aredifferent from each other according to sizes of a display drive currentnecessary for the respective organic EL devices 24 to obtain the samelight emission luminance.

Thereby, in a pixel circuit for specific color (in this case, inparticular, the blue color pixel 100B), the pixel pattern density isincreased, and thus the pattern defect rate is increased due to dust orthe like. Therefore, since the pattern defect rate is increased, themanufacturing yield is lowered.

The pixel configured of the pixels 100R, 100G, and 100B for R, G, and Bhas, for example, a planar structure as shown in FIG. 9. That is, in thesame manner as that of FIG. 5 of this embodiment, respective sizes 27R1,27G1, and 27B1 of the pixels 100R, 100G, and 100B for R, G, and B arerespectively set evenly within the pixel, and formation positions of thepixels 100R, 100G, and 100B for R, G, and B are respectively set evenlywithin the pixel.

Meanwhile, in the organic EL display unit 1 of this embodiment, asillustrated in FIG. 4, sizes of the color pixel circuits 26R, 26G, and26B respectively corresponding to the pixels 20R1, 20G1, and 20B1 for R,G, and B are respectively set unevenly within the pixel circuitaccording to the ratio of the size of the display drive currentnecessary for each organic EL device 24 to obtain the same lightemission luminance. Specifically, sizes of the color pixel circuits 26R,26G, and 26B are respectively set unevenly within the pixel circuitaccording to the area ratio between the color pixel circuits, of theopposing regions (overlapping regions) of the active layer (thepolysilicon layer P1) and the gate electrode (the second metal layer M2)in the drive transistors 22R1, 22G1, and 22B1 in the pixel circuits.Further, sizes of the color pixel circuits 26R, 26G, and 26B arerespectively set unevenly within the pixel circuit according to the arearatio between the color pixel circuits, of the accumulated capacitativeelements 23R1, 23G1, and 23B1.

Thereby, the pattern densities of the color pixel circuits respectivelycorresponding to the pixels 20R1, 20G1, and 20B1 for R, G, and B becomeeven to each other, even if the device sizes in the pixel circuits(specifically, the sizes of the drive transistors 22R1, 22G1, and 22B1and the sizes of the accumulated capacitative elements 23R1, 23G1, and23B1) are different from each other according to the size of the displaydrive current, the area of the foregoing opposing region, the area ofthe accumulated capacitative elements 23R1, 23G1, and 23B1 and the like.Thereby, increase of the pattern defect rate due to increase of thepixel pattern density in the pixel circuit for a specific color isavoided, and the pattern defect rate as the whole pixel circuit isdecreased.

As described above, in this embodiment, sizes of the color pixelcircuits 26R, 26G, and 26B respectively corresponding to the pixels20R1, 20G1, and 20B1 for R, G, and B are respectively set unevenlywithin the pixel circuit according to the ratio of the size of thedisplay drive current necessary for each organic EL device 24 to obtainthe same light emission luminance. Thus, the pattern densities of thecolor pixel circuits respectively corresponding to the pixels 20R1,20G1, and 20B1 for R, G, and B become even to each other, and thepattern defect rate as the whole pixel circuit is able to be decreased.Therefore, the manufacturing yield is able to be improved.

Specifically, sizes of the color pixel circuits 26R, 26G, and 26B arerespectively set unevenly within the pixel circuit according to the arearatio between the color pixel circuits, of the opposing regions(overlapping regions) of the active layer (polysilicon layer P1) and thegate electrode (second metal layer M2) in the drive transistors 22R1,22G1, and 22B1 in the pixel circuit. Thus, the foregoing effects areable to be obtained.

Further, sizes of the color pixel circuits 26R, 26G, and 26B arerespectively set unevenly within the pixel circuit according to the arearatio between the color pixel circuits, of the accumulated capacitativeelements 23R1, 23G1, and 23B1. Thus, the foregoing effects are able tobe obtained.

Further, respective sizes 27R1, 27G1, and 27B1 of the pixels 20R1, 20G1,and 20B1 for R, G, and B are respectively set evenly within the pixel,and the formation positions of the pixels 20R1, 20G1, and 20B1 for R, G,and B are set evenly within the pixel. Thus, existing patterns of theanode electrodes 281R1, 281G1, and 281B1 and the light emitting layers29R1, 29G1, and 29B1 are able to be used directly without anymodification. That is, while the characteristics of the luminance of thepanel and the like of the existing pattern are maintained, the patterndefect rate as the whole pixel circuit is able to be decreased.

Several other embodiments of the invention will be hereinafterdescribed. For the same elements as those in the foregoing firstembodiment, the same referential symbols are affixed thereto, and thedescription will be omitted as appropriate.

Second Embodiment

FIG. 10 illustrates a planar structural example of a pixel circuit layerand organic EL devices of pixels for each color 20R2, 20G2, and 20B2 ina self-light emitting display unit (organic EL display unit) accordingto a second embodiment of the invention.

In the pixel circuit layer of this embodiment, in the same manner asthat of the first embodiment, sizes of the color pixel circuits 26R,26G, and 26B respectively corresponding to the pixels 20R2, 20G2, and20B2 for R, G, and B are respectively set unevenly within the pixelcircuit according to a ratio between the color pixel circuits, of a sizeof the display drive current necessary for each organic EL device 24 toobtain the same light emission luminance, an area ratio between thecolor pixel circuits, of opposing regions between the polysilicon layerP1 and the second metal layer M2 in the drive transistors 22R1, 22G1,and 22B1 in the pixel circuit, or an area ratio between the color pixelcircuits, of the accumulated capacitative elements 23R1, 23G1, and 23B1.

Further, in the organic EL device of this embodiment, differently fromthe first embodiment, respective sizes 27R2, 27G2, and 27B2 of thepixels 20R2, 20G2, and 20B2 for R, G, and B are set unevenly within thepixel according to a ratio of sizes of the color pixel circuits 26R,26G, and 26B. Specifically, the arrangement pitches 27R2, 27G2, and 27B2of anode electrodes 281R2, 281G2, and 281B2 are respectively setunevenly between the color pixel circuits according to sizes of thecolor pixel circuits 26R, 26G, and 26B, and the arrangement pitches27R2, 27G2, and 27B2 of light emitting layers 29R2, 29G2, and 29B2 arerespectively set unevenly between the color pixel circuits according tosizes of the color pixel circuits 26R, 26G, and 26B.

Sizes of the color pixel circuits 26R, 26G, and 26B and sizes of thecolor pixels 27R2, 27G2, and 27B2 are expressed by the followingexpression 2 and expression 3:size of G color pixel 27G2<size of R color pixel 27R2<size of B colorpixel 27B2  2size of G color pixel circuit 26G<size of R color pixel circuit 26R<sizeof B color pixel circuit 26B  3

Next, a description will be given of operations and effects of theorganic EL display unit of this embodiment with reference to FIG. 11 toFIG. 14 in addition to FIG. 10 in comparison with the organic EL displayunit 1 of the foregoing first embodiment.

In the pixel circuit layer and the organic EL device 24 of the foregoingfirst embodiment, for example, as illustrated in FIG. 11, sizes 27R1,27G1, and 27B1 of the color pixels 20R1, 20G1, and 20B1 for R, G, and Bare set evenly within the pixel, and formation positions of the colorpixels 20R1, 20G1, and 20B1 for R, G, and B are set evenly within thepixel. Thus, for example, as illustrated in the figure, in some cases,an anode electrode of one color pixel (in this case, the anode electrode281R1 of the green pixel 20G1) and a signal line connected to a colorpixel adjacent thereto (in this case, the signal line DLb connected tothe blue pixel 20B1) are opposed to each other along the laminationdirection (overlapped). In this case, a parasitic capacity component Cpis generated in between.

That is, in the existing pixels 100R, 100G, and 100B, for example, asillustrated in a schematic cross sectional view in FIG. 12A, sizes(pitches) of the color pixel circuits 106R, 106G, and 106B correspondwith sizes (pitches) of the color pixels 27R1, 27G1, and 27B1. Thus,only inherent capacity components Cr101, Cg101, and Cb101 exist.Meanwhile, in the pixels 20R1, 20G1, and 20B1 of the foregoing firstembodiment, for example, as illustrated in a schematic cross sectionalview in FIG. 12B, sizes (pitches) of the color pixel circuits 26R, 26G,and 26B do not correspond with sizes (pitches) of the color pixels 27R1,27G1, and 27B1. Thus, the parasitic capacity component Cp is generatedin an overlapping region with an adjacent pixel. For example, FIG. 13illustrates a circuit diagram illustrating such a parasitic capacitycomponent Cp.

In the case where such a parasitic capacity component Cp is generated,for example, as illustrated in a timing waveform chart (timings t11 tot18) in FIG. 14, in a signal line (in this case, signal line DLg)corresponding to the pixel emitting light (in this case, the green pixel20G1), image quality disorder (crosstalk phenomenon) may be generatedbeing affected by coupling caused by the parasitic capacity componentCp. Specifically, in accordance with amplitude of the potential V (DLb)of the signal line DLb corresponding to the blue pixel 20B1, coupling(diving) is generated in the source of the green drive transistor 22from the blue signal potential Vsig through the parasitic capacitycomponent Cp. For example, as in the time period between the timings t14and t15 or between the timings t16 and t17, both the source potential Vsand the gate potential Vg in the green drive transistor 22 areincreased. In the case where a signal is written in the state that thegate potential Vg in the drive transistor 22 is increased, for example,as in the light emission time period T4 on and after the timing t18, thegate-to-source voltage Vgs is decreased compared to a case withoutcrosstalk, and image quality disorder (crosstalk phenomenon) isgenerated.

Therefore, in this embodiment, as illustrated in FIG. 10, sizes 27R2,27G2, and 27B2 of the color pixels 20R2, 20G2, and 20B2 are set unevenlyaccording to the ratio of sizes of the color pixel circuits 26R, 26G,and 26B. Specifically, arrangement pitches 27R2, 27G2, and 27B2 of theanode electrodes 281R2, 281G2, and 281B2 are respectively set unevenlyand arrangement pitches 27R2, 27G2, and 27B2 of the light emittinglayers 29R2, 29G2, and 29B2 are respectively set unevenly, according tothe ratio of sizes of the color pixel circuits 26R, 26G, and 26B.Thereby, the overlapping region between an anode electrode of one pixeland a signal line connected to a pixel adjacent thereto is notgenerated, and thus generation of the parasitic capacity component Cp isavoided.

As described above, in this embodiment, since sizes 27R2, 27G2, and 27B2of the color pixels 20R2, 20G2, and 20B2 are set unevenly according tothe ratio of sizes of the color pixel circuits 26R, 26G, and 26B, inaddition to the effects in the foregoing first embodiment, generation ofthe parasitic capacity component Cp is able to be avoided, and imagequality disorder (crosstalk phenomenon) is able to be eliminated.Accordingly, the pattern defect rate as the whole pixel circuit is ableto be decreased without affecting the image quality.

Third Embodiment

FIG. 15 illustrates a planar structural example of color pixels 20R3,20G3, and 20B3 and color pixel circuits respectively correspondingthereto, in a self-light emitting display unit (organic EL display unit)according to a third embodiment of the invention.

In the pixel circuit layer of this embodiment, in the same manner asthat of the foregoing first embodiment, sizes of the color pixelcircuits 26R, 26G, and 26B respectively corresponding to the pixels20R3, 20G3, and 20B3 for R, G, and B are respectively set unevenlywithin the pixel circuit according to a ratio of a size of the displaydrive current necessary for each organic EL device 24 to obtain the samelight emission luminance, an area ratio between the color pixelcircuits, of opposing regions (overlapping regions) of the polysiliconlayer P1 and the second metal layer M2 in the drive transistors 22R1,22G1, and 22B1 in the pixel circuits, or an area ratio between the colorpixel circuits, of the accumulated capacitative elements 23R1, 23G1, and23B1.

Further, in this embodiment, in the same manner as that of the foregoingfirst embodiment, the sizes of the color pixels 20R3, 20G3, and 20B3 areset evenly within the pixel.

However, in the organic EL device of this embodiment, differently fromthe foregoing first embodiment and the foregoing second embodiment,formation positions of the color pixels 20R3, 20G3, and 20B3 are setunevenly within the pixel according to a ratio of sizes of the colorpixel circuits 26R, 26G, and 26B. Specifically, formation positions inthe anode electrodes 281R1, 281G1, and 281B1 and the light emittinglayers 29R1, 29G1, and 29B1 are set so that an anode electrode of onepixel and a signal line connected to a pixel adjacent thereto are notopposed to each other along the lamination direction (overlapping regionis not generated), and an auxiliary wiring section 280-3 electricallyconnected to the cathode electrode 282 is formed in a niche in theformation regions of the anode electrodes 281R1, 281G1, and 281B1 andthe light emitting layers 29R1, 29G1, and 29B1.

Thereby, differently from the foregoing first embodiment, theoverlapping region between an anode electrode of one pixel and a signalline connected to a pixel adjacent thereto is not generated. Thus,generation of the parasitic capacity component Cp is avoided.

Further differently from the foregoing second embodiment, since thesizes of the color pixels 20R3, 20G3, and 20B3 (specifically, sizes ofthe light emitting layers 29R1, 29G1 and 29B1 and the like) are setevenly within the pixel. Thereby, difference of life time according todifference of view angle characteristics and difference of currentdensities for every color is avoided. Further, disorder of white balanceand difference of vertical line sizes for R, G, and B are avoided.

Accordingly, in this embodiment, since the sizes of the color pixels20R3, 20G3, and 20B3 (specifically, sizes of the light emitting layers29R1, 29G1 and 29B1 and the like) are set evenly within the pixel, inaddition to the effects in the foregoing second embodiment, the patterndefect rate as the whole pixel circuit is able to be decreased with noinfluence on the image quality without changing life characteristics andthe like according to difference of view angle characteristics anddifference of current densities for every color.

Fourth Embodiment

FIG. 16 illustrates a planar structural example of color pixels 20R4,20G4, and 20B4 and color pixel circuits respectively correspondingthereto, in a self-light emitting display unit (organic EL display unit)according to a fourth embodiment of the invention. FIG. 17 illustrates aplanar structural example of color pixels 20R5, 20G5, and 20B5 and colorpixel circuits respectively corresponding thereto, in another self-lightemitting display unit (organic EL display unit) according to thisembodiment.

In the structural example illustrated in FIG. 16, drive transistors22R2, 22G2, and 22B2 of the respective pixels 20R4, 20G4, and 20B4 arerespectively arranged in their own color pixel regions, in the casewhere a color pixel circuit is arranged evenly for every pixel for R, G,and B (in the case of supposing that pixel sizes 106R, 106G, and 106Bare set evenly). That is, each of the drive transistors 22R2, 22G2, and22B2 is located within an evenly-divided region defined as a color pixelcircuit region which is to be generated when the pixel circuit is evenlydivided into color pixel circuits, the evenly-divided regioncorresponding to the color pixel circuit to which each of the drivetransistors actually belongs.

Further, in the structural example illustrated in FIG. 17, accumulatedcapacitative elements 23R2, 23G2, and 23B2 of the respective pixels20R5, 20G5, and 20B5 are respectively arranged in their own color pixelregions, in the case where a color pixel circuit is arranged evenly forevery pixel for R, G, and B (in the case of supposing that pixel sizes106R, 106G, and 106B are set evenly). That is, each of the accumulatedcapacitative elements 23R2, 23G2, and 23B2 is located within anevenly-divided region defined as a color pixel circuit region which isto be generated when the pixel circuit is evenly divided into colorpixel circuits, the evenly-divided region corresponding to the colorpixel circuit to which each of the accumulated capacitative elementsactually belongs.

Due to the foregoing structures, differently from the foregoing firstembodiment, the overlapping region between an anode electrode of onepixel and a signal line connected to a pixel adjacent thereto is notgenerated. Accordingly, generation of the parasitic capacity componentCp is avoided.

As described above, in this embodiment, each of the drive transistors22R2, 22G2, and 22B2 or each of the accumulated capacitative elements23R2, 23G2, and 23B2 is located within an evenly-divided region definedas a color pixel circuit region which is to be generated when the pixelcircuit is evenly divided into color pixel circuits, the evenly-dividedregion corresponding to the color pixel circuit to which each of thedrive transistors or each of the accumulated capacitative elementsactually belongs. Thus, in addition to the effects of the foregoingfirst embodiment, generation of the parasitic capacity component Cp isable to be avoided, and disorder of image quality (crosstalk phenomenon)is able to be eliminated. In result, the pattern defect rate as thewhole pixel circuit is able to be decreased with no influence on theimage quality.

Also, each of the signal lines DLr, DLg, and DLb corresponding to eachpixel may be located within an evenly-divided region defined as a colorpixel circuit region which is to be generated when the pixel circuit isevenly divided into color pixel circuits, the evenly-divided regioncorresponding to the color pixel circuit to which each of the signallines actually belongs. In this case, disorder of image quality(crosstalk phenomenon) is able to be eliminated, and the pattern defectrate as the entire whole circuit is able to be decreased with noinfluence on the image quality as well.

Further, more generally, if, regarding at least one or more groupsselected from the three groups of the drive transistors 22R2, 22G2, and22B2, the accumulated capacitative elements 23R2, 23G2, and 23B2, andthe signal lines DLr, DLg, and DLb, each element in one group is locatedwithin an evenly-divided region defined as a color pixel circuit regionwhich is to be generated when the pixel circuit is evenly divided intocolor pixel circuits, the evenly-divided region corresponding to thecolor pixel circuit to which each element actually belongs, the effectof this embodiment is able to be obtained.

APPLICATION EXAMPLES

Next, a description will be given of application examples of theself-light emitting display unit described in the foregoing first tofourth embodiments with reference to FIG. 18 to FIG. 22G. The self-lightemitting display unit described in the foregoing first to fourthembodiments (specifically, the organic EL display unit) is able to beapplied to an electronic device in any field for displaying a picturesignal inputted from outside or a picture signal generated inside as animage or a picture, such as a television device, a digital camera, anotebook personal computer, a portable terminal device such as a mobilephone, and a video camera.

First Application Example

FIG. 18 is an appearance of a television device to which the self-lightemitting display unit of the foregoing embodiments is applied. Thetelevision device has, for example, a picture display screen section 510including a front panel 511 and a filter glass 512. The picture displayscreen section 510 is configured of the self-light emitting display unitaccording to the foregoing embodiments and the like.

Second Application Example

FIGS. 19A and 19B are an appearance of a digital camera to which theself-light emitting display unit of the foregoing embodiments isapplied. The digital camera has, for example, a light emitting sectionfor a flash 521, a display section 522, a menu switch 523, and a shutterbutton 524. The display section 522 is configured of the self-lightemitting display unit according to the foregoing embodiments.

Third Application Example

FIG. 20 is an appearance of a notebook personal computer to which theself-light emitting display unit of the foregoing embodiments isapplied. The notebook personal computer has, for example, a main body531, a keyboard 532 for operation of inputting characters and the like,and a display section 533 for displaying an image. The display section533 is configured of the self-light emitting display unit according tothe foregoing embodiments.

Fourth Application Example

FIG. 21 is an appearance of a video camera to which the self-lightemitting display unit of the foregoing embodiments is applied. The videocamera has, for example, a main body 541, a lens for shooting an object542 provided on the front side face of the main body 541, a start/stopswitch in shooting 543, and a display section 544. The display section544 is configured of the self-light emitting display unit according tothe foregoing embodiments.

Fifth Application Example

FIGS. 22A to 22G are an appearance of a mobile phone to which theself-light emitting display unit of the foregoing embodiments isapplied. In the mobile phone, for example, an upper package 710 and alower package 720 are jointed by a joint section (hinge section) 730.The mobile phone has a display 740, a sub-display 750, a picture light760, and a camera 770. The display 740 or the sub-display 750 isconfigured of the self-light emitting display unit according to theforegoing embodiments.

While the invention has been described with reference to the first tofourth embodiments and the application examples, the invention is notlimited to the foregoing embodiments and the like, and variousmodifications may be made.

For example, in the foregoing embodiments and the like, while thedescription has been given of the case that sizes of the color pixelcircuits 26R, 26G, and 26B or sizes of the color pixels 27R2, 27G2, and27B2 are expressed by the above-mentioned expressions 1 to 3,embodiments of uneven arrangement are not limited thereto.

Further, for example, as the pixel circuit in a pixel 20-1 illustratedin FIG. 23 to FIG. 25, the invention is able to be applied to a case inwhich a parasitic capacity component 240 is generated in parallel withthe organic EL device 24 (capacity values are different for everycolor), and the difference of the capacity values for every color isadjusted by two accumulated capacitative elements 23 a and 23 b and thelike.

In addition, in the foregoing embodiments and the like, the descriptionhas been given of the structure composed of the pixels for R, G, and B(in the case of the three color pixels). However, the invention is notlimited to such a structure. That is, for example, the invention is ableto be applied to a structure having pixels for a voluntarily number ofcolors such as a case of four color pixels obtained by adding w (white)pixels thereto, a case of two color pixels, and a case of five colorpixels.

Further, in the foregoing embodiments and the like, the description hasbeen given of the case that the self-light emitting device is an organicEL device. However, the invention is also applied to a self-lightemitting display unit using other self-light emitting device (forexample, an inorganic EL device or LED) or the like.

The present application contains subject matter related to thatdisclosed in Japanese Priority Patent Application JP 2008-159169 filedin the Japan Patent Office on Jun. 18, 2008, the entire content of whichis hereby incorporated by reference.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A self-light emitting display unit comprising: apixel layer in which a plurality of pixels are formed, each pixel of theplurality of pixels comprising a plurality of color sub-pixels that eachhave a color self-light emitting element; and a pixel circuit layer inwhich a plurality of pixel circuits are formed, each pixel circuit ofthe plurality of pixel circuits comprising a plurality of colorsub-pixel circuits which drive the color sub-pixels, respectively,wherein sizes of the color sub-pixels are set unevenly and such thatthere is no overlapping between an anode electrode of any colorsub-pixel and a signal line of any color sub-pixel circuit.
 2. Theself-light emitting display unit of claim 1, wherein the plurality ofcolor sub-pixels of a given pixel of the plurality of pixels comprise ablue sub-pixel, a red sub-pixel, and a green sub-pixel, and the size ofthe blue sub-pixel is greater than the size of the red sub-pixel and thesize of the green sub-pixel.
 3. The self-light emitting display unit ofclaim 2, wherein the size of the red sub-pixel is greater than the sizeof the green sub-pixel.
 4. The self-light emitting display unit of claim1, wherein the plurality of color sub-pixels of a given pixel of theplurality of pixels comprise a blue sub-pixel, a red sub-pixel, and agreen sub-pixel, and a size of an anode electrode of the blue sub-pixelis greater than a size of the anode electrode of the red sub-pixel and asize of the anode electrode of the green sub-pixel.
 5. The self-lightemitting display unit of claim 2, wherein a size of an anode electrodeof the blue sub-pixel is greater than a size of the anode electrode ofthe red sub-pixel and a size of the anode electrode of the greensub-pixel.
 6. A self-light emitting display unit comprising: a pixellayer in which a plurality of pixels are formed, each pixel of theplurality of pixels comprising a plurality of color sub-pixels that eachhave a color self-light emitting element; and a pixel circuit layer inwhich a plurality of pixel circuits are formed, each pixel circuit ofthe plurality of pixel circuits comprising a plurality of colorsub-pixel circuits which drive the color sub-pixels, respectively,wherein sizes of the color sub-pixels are set unevenly and such thatthere is no overlapping between an anode electrode of a given colorsub-pixel and a signal line of the color sub-pixel circuit that drivesthe given color sub-pixel.
 7. The self-light emitting display unit ofclaim 6, wherein the plurality of color sub-pixels of a given pixel ofthe plurality of pixels comprise a blue sub-pixel, a red sub-pixel, anda green sub-pixel, and the size of the blue sub-pixel is greater thanthe size of the red sub-pixel and the size of the green sub-pixel. 8.The self-light emitting display unit of claim 7, wherein the size of thered sub-pixel is greater than the size of the green sub-pixel.
 9. Theself-light emitting display unit of claim 6, wherein the plurality ofcolor sub-pixels of a given pixel of the plurality of pixels comprise ablue sub-pixel, a red sub-pixel, and a green sub-pixel, and a size of ananode electrode of the blue sub-pixel is greater than a size of theanode electrode of the red sub-pixel and a size of the anode electrodeof the green sub-pixel.
 10. The self-light emitting display unit ofclaim 7, wherein a size of an anode electrode of the blue sub-pixel isgreater than a size of the anode electrode of the red sub-pixel and asize of the anode electrode of the green sub-pixel.
 11. An electronicdevice comprising the self-light emitting display unit of claim
 6. 12.The electronic device of claim 11, wherein the electronic device is amobile-phone.
 13. The electronic device of claim 11, wherein theelectronic device is a camera.
 14. The electronic device of claim 11,wherein the electronic device is a portable computer.